ABSTRACT
INTRODUCTION: Virtual 3-dimensional (3D) models obtained by scanning of physical casts have become an alternative to conventional dental cast analysis in orthodontic treatment. If the precision (reproducibility) of virtual 3D model analysis can be further improved, digital orthodontics could be even more widely accepted. The purpose of this study was to clarify the influence of "standardization" of the target points for dental cast analysis using virtual 3D models. Physical plaster models were also measured to obtain additional information. METHODS: Five sets of dental casts were used. The dental casts were scanned with R700 (3Shape, Copenhagen, Denmark) and REXCAN DS2 3D (Solutionix, Seoul, Korea) scanners. In this study, 3 system and software packages were used: SureSmile (OraMetrix, Richardson, Tex), Rapidform (Inus, Seoul, Korea), and I-DEAS (SDRC, Milford, Conn). RESULTS: Without standardization, the maximum differences were observed between the SureSmile software and the Rapidform software (0.39 mm ± 0.07). With standardization, the maximum differences were observed between the SureSmile software and measurements with a digital caliper (0.099 mm ± 0.01), and this difference was significantly greater (P <0.05) than the 2 other mean difference values. Furthermore, the results of this study showed that the mean differences "WITH" standardization were significantly lower than those "WITHOUT" standardization for all systems, software packages, or methods. CONCLUSIONS: The results showed that elimination of the influence of usability or habituation is important for improving the reproducibility of dental cast analysis.
Subject(s)
Imaging, Three-Dimensional/statistics & numerical data , Models, Dental/standards , User-Computer Interface , Algorithms , Calcium Sulfate/chemistry , Computer Simulation , Computer-Aided Design/standards , Computer-Aided Design/statistics & numerical data , Dental Materials/chemistry , Fiducial Markers , Humans , Image Processing, Computer-Assisted/statistics & numerical data , Models, Dental/statistics & numerical data , Reproducibility of Results , Software , Surface PropertiesABSTRACT
AIM: To understand the efficiency of SureSmile treatment vs conventional treatment. METHODS: First, 12,335 completed patient histories representing different treatment philosophies and geographically diverse practices were collected. Included were 9,390 SureSmile patients and 2,945 conventional patients. Variables in these patient records included: (1) treatment time, months from bonding to debonding; (2) malocclusion class, Angle Class I, II, or III; (3) patient age, adolescents (< 18 years) or adults (≥ 18 years); and (4) patient visits, total number of treatment visits. Nonparametric regression tests were used to analyze the data. RESULTS: The median treatment time for the SureSmile patient pool (15 months) was 8 months shorter than that of the conventional patient pool (23 months). The median care cycle length of Class II SureSmile patients (13 months) was 2 months shorter than that of Class I SureSmile patients (15 months) and 3 months shorter than that of Class III SureSmile patients (16 months). SureSmile patients (14 visits) had four fewer median treatment visits than conventional patients (18 visits). All results were significant at P = .001. No significant differences were noted between the median care cycle lengths of adolescents and adults. CONCLUSION: This study found that SureSmile treatment facilitates more timely care than conventional treatment. Further prospective studies are required to elucidate the effectiveness of SureSmile treatment.
Subject(s)
Malocclusion, Angle Class I , Malocclusion , Age Factors , Humans , Malocclusion, Angle Class I/therapy , Malocclusion, Angle Class II/therapy , Prospective StudiesABSTRACT
This study evaluates Class I, 4-premolar-extraction patients who were treated with the edgewise appliance by 1 practitioner, according to the philosophy of Tweed, and who had been out of retention a minimum of 5 years. The sample includes 32 patients, who started treatment at an average age of 12.8 years and who were examined a mean of 15 years posttreatment (11.7 years postretention). Cephalometric and model analyses were conducted to evaluate treatment and posttreatment tooth movements. The results showed that irregularity, as measured by the irregularity index, decreased 5.3 mm during treatment and increased 0.7 mm (SD 1.1 mm) during the posttreatment period. Eighty percent of the patients had satisfactory (<3.5 mm) mandibular incisor alignment over 10 years postretention, and none was in the severe category (>6.5 mm). Mandibular intercanine width increased (1.7 mm) during treatment, whereas intermolar width decreased (-2.1 mm). Maxillary molar widths remained unchanged posttreatment, and mandibular intercanine width decreased 1.4 mm from immediately posttreatment to postretention. Arch lengths decreased during treatment because of molar protraction and incisor retraction. Mandibular arch length continued to decrease posttreatment (-1.4 mm) because of mesial molar movement rather than distal incisor movement. Satisfactory long-term results can be achieved for most Class I, 4-premolar-extraction patients for whom evidence-based treatment objectives-including minimal alteration of the mandibular arch form and the retraction and uprighting or maintenance of mandibular incisors in their original position-have been met.
